Fig. 6.

Immature secretory granules and misregulated exocytosis and SG genes in the Aldh1b1 ^tm1lacZ null islets. (a–d) Transmission electron microscopy revealed that affected Aldh1b1 ^tm1lacZ null beta cells have 30% (c) fewer type 1 SGs (mature granules shown by black arrows in a, b) and 22% (d) more type 2 SGs (immature granules shown by white arrows in a, b). Results are from three animals per genotype and islet cells were scored in double blind experiments for granule number and type (black bars, wild-type; grey bars, null). (e) z score heat maps showed misregulated expression of several genes involved in SG formation and exocytosis. Values are means ± SEM. *p < 0.01 for indicated comparison. Heat map, *p _adj ≤ 0.05: at the left side of the heat map * refers to comparisons at P1 whereas at the right side it refers to comparisons at WK 8. Scale bar, 1 μm. WK, week; WT, wild-type